Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New rapid test for evaluating fluoride in drinking water

01.04.2014

The addition of fluoride to drinking water or toothpaste is widespread and is mainly used for dental health and as a preventative measure against bone diseases.

However, an excessively high concentration of fluoride can lead to health problems. Clear symptoms of this fluorosis, that occurs in developing countries in particular, are brownish-yellow stains on the teeth.

Fluorinated drinking water is not being monitored everywhere so that children in particular can ingest too much fluoride. BAM Federal Institute for Materials Research and Testing has developed a very simple rapid colour test, which can help determine the fluoride concentration more easily in the future.

A change in the colour of a paper strip shows how much fluoride is dissolved in the water, similar to a litmus test to determine the pH value. The concentration is indicated by yellow-green dots, the darker the spot, the more fluoride is present. A dye developed by BAM is used in the procedure.

"This BODIPY amidothiourea dye is applied as a small spot to a strip of nitrocellulose that responds to the fluoride ion" says Pichandi Ashokkumar, who, together with Knut Rurack, has developed the test.

The paper strip is then immersed in a glass of water for example. The analyst can read the concentration by the change in the perceived colour and the test strip is reusable because of the particular chemical dye chosen. As simple as it sounds, it was very difficult to implement because fluoride is bound to thiocarbamide by hydrogen bonds.

Bonding triggers an electron transfer, which weakens the dye’s fluorescence so that the dye will appear darker. "The trick then was to develop a process that, in spite of the aqueous environment, still binds the fluoride and not the water's oxygen to the thiocarbamide" says project manager Knut Rurack. As the tests indicate, the scientists have succeeded. In order to evaluate the colour change better than with the human eye, the test strip’s colour may also be detected with the built-in camera of a mobile phone.

Fluorination of drinking water is common practice. In Europe this is practiced in the UK, Ireland and Switzerland and the U.S. also fluorinates the drinking water. In 2011, the U.S. Environmental Protection Agency (EPA) reduced the benchmark for fluoride in drinking water from 1 to 0.7 parts per million (ppm) and thus joined other countries.

The detection limit of the new fluoride test is 0.2 ppm. The test was conducted using different water samples, including tap and sea water. "The test is not disturbed by other ions in tap water or salt water," says Rurack. However, too high a concentration of phosphate, as in some toothpastes, may cause problems. The scientists envisage a potentially large field of application for their testes especially in Asia and Africa.

Contact:
Dr. rer. nat. Knut Rurack
Department 1 Analytical Chemistry; Reference Materials
Email: Knut.Rurack@bam.de

"Test-Strip-Based Fluorometric Detection of Fluoride in AqueousMedia with a BODIPY-Linked Hydrogen-Bonding Receptor", Pichandi Ashokkumar, Hardy Weißhoff, Werner Kraus and Knut Rurack, Angew. Chem. Int. Ed. 2014, 53, 2225-2229

Dr. Ulrike Rockland | idw - Informationsdienst Wissenschaft

Further reports about: BAM Protection concentration drinking glass ions phosphate procedure

More articles from Life Sciences:

nachricht Researchers uncover protein-based “cancer signature”
05.12.2016 | Universität Basel

nachricht The Nagoya Protocol Creates Disadvantages for Many Countries when Applied to Microorganisms
05.12.2016 | Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

IHP presents the fastest silicon-based transistor in the world

05.12.2016 | Power and Electrical Engineering

InLight study: insights into chemical processes using light

05.12.2016 | Materials Sciences

High-precision magnetic field sensing

05.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>